Collimateur Chretien - French optical gunsight

[MikeW]

Has anyone come across the French telescopic gunsight, the Collimateur Chretien? Fitted to some Nieuports apparently.

Descriptions, or photographs?


Mike

[Jim]

It doesn't sound very practical to me. Have you ever tried looking at a moving object through binoculars while you are running? There is no way to keep the object in the magnified field of view. It would also be pretty difficult to lead an aircraft with your fire. Unless you are approaching directly head on or straight up the guy's six you have to lead the target since he is moving so fast that by the time your bullets arrive at his location he is no longer there.

Do you know if any victories were ever claimed using this gunsight?

[FinnN]

If I remember correctly the types of telescopic gunsights you see on inter-war and early WW2 aircraft were mostly used for identifying aircraft or other targets from a distance rather than actual aiming. I'd be suprised if the WW1 ones were intended to be used any differently - unless there was a lot of wishful thinking going on!

I had a quick cursory look through de Brunoff's "L'Aéronautique Pendant la Guerre Mondiale" and couldn't find anything. The closest I could find is a labelled cutaway photograph of the cockpit area of a plane with the mounting for a gunsight, but the gunsight itself is missing. Judging by the size and shape of the mounting it looks like it was for a telescopic one - I'll scan it in and post it here if that's of any use to you.

The Germans certainly had a telescopic sight - the Oigee - which I think was originally for observers guns. An issue of "L'Aérophile" from 1918 has some reasonable diagrams of this in it. Unfortunately I only have that year so I can't say if there'd be any descriptions of French ones in other issues, although in general I find from my very limited experience that the various magazines of the day had far more information on the enemy than on friendly equipment.

Have fun
Finn

[MikeW]

Jim,

optical sights were very common, never heard of the Aldis?



I have a reference to a British pilot flying a Nieuport fitted with the Collimateur Chretien sight and commenting that it was better than the Aldis.

From Harry Woodman's "Early Aircraft Armament":


He mentions Zeiss, Goertz and Busch optical sights, then:

"The Oigee firm produced a telescopic tubular sight which was issued in 1918. German pilots often fitted captured Aldis sights to their machines, while the French adopted a collimateur clair, Chretien de 25mm which was similar to the Aldis".

But that's all I can find.

[FinnN]

Here's the cutaway photo (of a Spad I think, but I'm sure I'll be corrected there) - the gunsight mounting is the area marked 'E' just inboard of the right hand gun.

[FinnN]

And just because it's come up, here's the two diagrams of the Oigee from L'Aérophile. There's also a little bit of accompanying text that describes how it works, nothing very exciting though.

Have fun
Finn

[Jim]

Thanks Mike, I believe you but it still sounds fairly sketchy as to how well it could work in practice. Especially since you would also have to have your aircraft kept pointed directly at another aircraft to use it which is no easy thing when you are riding in a moving machine that has a 360 degree axis and are being buffeted by wind and the vibration of your motor all while having to keep your neck on a constant swivel to be sure the other guy was not working his way around to get a shot at you. Do you know of any claims of victories while using it?

[MikeW]

Jim,

you are thinking in terms of a telescopic sight fitted to a rifle. The Aldis did not greatly magnify a distant image like a conventional telescope.

Without the intense magnification there is a much wider angle of view, I have seen a photograph of an image in an Aldis and it certainly gave the pilot the ability to "lead" the target. The pilot did not have to put his eye to the sight but could see the view from a fairly wide angle.

Most successful combats took place when the unsuccessful pilot of the encounter did not realise that the successful pilot was sticking his gun muzzle in his ear. By the time he did realise, it was usually too late.

[MikeW]

Here is an example of the view through an Aldis at 100 yards range, not with the eye pressed up to the "telescope" but from an angle.

I believe this shot originates from Aldis technical literature.

[hubbabubba]

There is an ancient thread discussing optical gunsight; (http://www.theaerodrome.com/forum/ar...hp/t-6706.html).
You will find it very informative! Go have a looK!